Process for dyeing polyester textiles with anthraquinone dyestuffs by thermofixation

ABSTRACT

Anthraquinone dyes for dyeing polyester fabric are made by the reaction of an arylamine, such as aniline, with a dichlorochrysazin in which one of the chlorine atoms is in a nonperi position, the reaction being conducted in the presence of boric acid. This class of anthraquinone dyes, when appropriately dispersed, produces blue-green dyeings on aromatic polyester fabrics with excellent substantivity, outstanding sublimation fastness, and good fastness to light. The dyes are applied to polyesters, such as polyethylene terephthalate, preferably by thermofixation methods.

United States Patent [191 Botros PROCESS FOR DYEING POLYESTER TEXTILES WITH ANTHRAQUINONE DYESTUFFS BY TI-IERMOFIXATION [75] Inventor: Raouf Botros, Lock Haven, Pa.

[73] Assignee: American Aniline Products, Inc., Paterson, NJ.

22 Filed: .lan.3 l, 1972 21 Appl. No.: 222,361

[52] U.S. Cl 8/21 C, 8/39, 260/378,

4/1972 Booth et al. 260/378 [45] .lan. I5, 1974 OTHER PUBLICATIONS Primary Examiner-Leon D. Rosdol Assistant Examiner-T. J. Herbert, .lr. Att0meyArmstrong & Wegner [57] ABSTRACT Anthraquinone dyes for dyeing polyester fabric are made by the reaction of an arylamine, such as aniline, with a dichlorochrysazin in which one of the chlorine atoms is in a non-peri position, the reaction being conducted in the presence of bdric acid. This class of anthraquinone dyes, when appropriately dispersed, produces blue-green dyeings on aromatic polyester fabrics with excellent substantivity, outstanding sublimation fastness, and good fastness to light. The dyes are applied to polyesters, such as polyethylene terephthalate, preferably by thermofixation methods.

10 Claims, No Drawings PROCESS FOR DYEING POLYESTER TEXTILES WITH ANTHRAQUINONE DYESTUFFS IBY THERMOFIXATION BACKGROUND OF THE INVENTION Among the polyester fibers, those based on polyethylene terephthalate continue to be the most important, although fibers based on l,4-dimethylcyclohexane terephthalate have become commercially available. Developments in both homo-and copolyesters have continued and many modified versions of polyethylene terephthalate have recently appeared on the market.

Disperse dyes are ordinarily applied to aromatic polyester fibers by carrier dyeing, pressure dyeing and thermo-fixationmethods. The fundamental thermofixation method, described in us. Pat. 2,663,612, is adaptable for dyeing of both polyester and mixed polyester-cotton blends and permits rapid and economical production of a high volume of dyed fabric. The use of thermofixation methods requires dyes with a high diffusion rate and good solubility in polyester fibers in order to fully utilize the dye and to obtain level and reproducible dyeings. Unfortunately, dyes with the high diffusion rate required for thermofixation are often easily extracted into the finishing agents during conventional after-treatments such as a durable press finish curing operation. Because of this problem, useful dyes should have a high diffusion rate in polyester fibers at the thermofixation temperature (400-430F), a low diffusion rate at the durable press curing temperature (300350F) and high solubility in polyester fibers.

I have discovered certain l,4-bis(arylamino)haloanthraquinone dyes which provide dyeings of a deep blue-green hue when applied to polyester textile material by thermo-fixation methods. Dyed fabric provided wherein Z is a non-peri chlorine or bromine, R and R are hydrogen, chlorine, bromine, lower alkyl or lower alkoxy and n has a value of 1-3.

The dyes of the invention are made by admixing 4,)(-

5 Di-chlorochrysazin, an aryl amine of the formula in which R and n, are defined above and a catalytic amount of boric acid, lower alkyl borates or boron oxides. The mixture is allowed to react at an elevated temperature of 125C up to the reflux temperature of the mixture until the reaction is substantially complete and the product is recovered therefrom by filtration.

The dyes of the invention are preferably applied to polyester textile material, including mixed blends of polyester-cotton, by a thermofixation process involving padding the polyester textile material with a dilute dispersion of the product dye, drying the padded cloth to remove water, and heat-curing the dried material at a temperature of 350430F for a period of about 2 minutesor less.

DETAILED DESCRIPTION The starting material for use in the invention is a dihalochrysazin made by treating chrysazin with sulfuryl chloride or bromine in nitrobenzene at reflux for several hours. The resulting product is a 4,x-

dihalochrysazin, in which X may be the 6-position of by the invention can be after-treated as required with excellent results.

SUMMARY OF THE INVENTION NIH--- v E R2) the anthraquinone nucleus. The literature reports the dichlorination of chrysazin (l,S-dihydroxyanthraquninone) by treating it with chlorine in aqueous acetic acid at C; DRP 127,669 Frdl. 6 328. An alternate process is described in DRP'l72,300, Frdl. 8 274, in which chrysazin is treated in aqueous sulfuric acid at with potassium chlorate and sodium chloride. The products of both processes are said to be 4,5- dichlorochrysazin. However, according to the experimental results using my recommended halogenation procedure, one of the halogens is in a non-peri position. Thus, the dihalochrysazine produced provides a unique product when treated according to the method of the invention.

The 4,X-dihalochrysazin is allowed to react with an aryl amine of the formula:

in which R and n are as defined above. Suitable aryl amines for use in the reaction include aniline, ptoluidine, m-toluidine, p-anisidine, p-chloroaniline, pphenetidine and m-chloroaniline. The various xylidines and mesidine are also useful in the reaction.

The reaction is conducted in the presence of a catalytic amount of boric acid, alower alkyl borate, such as triethyl or trimethyl borate or a boric oxide, generally between 0.5 5 percent by'weight, based on the weight of the reaction mixture. The presence of the boric acid or a borate ester or oxide is essential in order to provide the novel products of the invention. If the same reactants are mixed together in the presence of an alkaline acid-binding agent and a copper salt, both halogens are replaced by an aryl amino group and the resulting product is, l,8-dihydroxy-4,X-bis- (arylamino)anthra-quinone. Such products are distinctly blue in hue and virtually no residual chlorine can be detected by standard analytical methods.

The reaction of the present invention is conducted at an elevated temperature between 125C and the reflux temperature of the reaction mixture. It is convenient to use an excess of the amine reactant as areaction medium, although it is possible to use substantially stoichimetric amounts of reactants in the presence of an inert solvent. After completion of the reaction, which generally takes between -24 hours, the product is separated and recovered by conventional methods.

A particularly convenient way to recover the product in a purified form is to dilute the reaction mixture with methanol or denatured alcohol in an amount of 100 to 300 percent based on the volume of the reaction mixture. In this method of product recovery, the reaction mixture is first cooled, the alcohol is added and the mixture is reheated to reflux. It is then allowed to cool gradually to room temperature, filtered, and the product collected on the filter is washed again with alcohol and thereafter, oven-dried. When suitable, the alcohol solution of the reaction mixture may be filtered hot. Further purification of the product may be achieved by digestion of the cake in 5 parts by weight of dimethyl formamide at room temperature, filtering and washing again with hot water.

- The presence of the residual non-peri chlorine provides a reactive position which can be utilized in the preparation of other new and useful products. For example, the products of the invention can be further reacted with a compound of the formula RXl-l in which R is aryl, e.g., phenyl, lower alkyl phenyl, lower alkoxy phenyl or halophenyl; lower alkyl or a hydrocarbon residue of a heterocycle; and X is oxygen or sulfur.

The reaction can be summarized as follows:

(l)H IIIHAR RXH halogerhE ll 0 NEAR C|JH NHAR RX H halogen ll 0 NEAR Specific useful compounds are l-propanethiol; lpentanethiol; a-toluenethiol; 2-mercaptoethanol; 1,2- ethanedithiol; benzenethiol; p-chlorobenzenethiol; ptoluenethiol; 2,4-di-chlorobenzenethiol; 4-chloro-otoluenethiol; p-methoxybenzenethiol; 4-chloro-otoluenethiol; p-benzenedithiol; pyridine-Z-thiol; thiophene-2-thiol; Z-mercaptobenzothiazole; 2- mercaptothiazole; methanol; ethanol; l-propanol; 2- methyl-l-propanol; 2-ethyl-l-hexanol; l-dodecanol; ethylene glycol; glycerol; benzyl alcohol; cyclohexanol; 1,4-cyclohexanediol; phenol; o,m, or p-cresol; 2,4- xylenol; 2,5-xylenol; p-chlorophenol; m-bromophenol; p-hydroxyacetanilide; p-hydroxyacetophenone; phydroxybenzonitrile; l-naphthol; Z-naphthol; 4-(mefiw- P l a2? -.x.19hm q m t a a To prepare the product forv application to the polyester substrates the product must be suitably dispersed. This may be done in any of several well-known methods, milling as in a ball-mill with dispersing agents such as lignin sulfonic acid materials, for instance. The resultant aqueous dispersion can be dried, as in a spraydryer, or preserved and used as a paste. Standardization to any desired lower strength can be done with inert colorless diluents such as inorganic salts for powders, or water for pastes. Other materials such as preservatives, foam-control agents, and wetting agents may be added as desired.

Dispersed pastes are made by wet milling the dye in conventional equipment in the presence of a dispersing agent, preferably sodium lignin sulfonate or sodium alkylnaphthalene sulfonate. Various other commercially available dispersing agents, such as sodium salts of carboxylated polyelectrolytes and the naphthalene sulfonates; e.g., the condensation products of sulfonated naphthalene and formaldehyde, such as sodium dinaphthylmethane disulfonate, are conveniently used.

The oil disperse paste may be cut or standardized to a standard strength with water. The final color content of the finished paste averages from l040 percent by weight (pure color) active dye base.

Disperse powders are prepared by wet milling color in the presence of a dispersant, such as those mentioned hereabove, in equipment such as a ball mill, Werner-Pfleiderer mill or attritor. The dispersed material is oven or spray dried and micropulverized if necessary to provide the dispersed powder. The color is cut or standardized to a standard strength in a blender with a diluent, such as sodium sulfate or dextrin. A wetting agent, such as sodium cetyl sulfate or an alkylphenoxy polyethanol may be added to aid in wetting out the product when it is placed in the dye bath. Disperse powders are usually cut or standardized to 25-60 percent by weight color content (pure color).

The dye is preferably applied to the aromatic polyester fiber by thermofixation methods, such as the Thermosol process. This process involves padding the cloth with a dilute dye dispersion, followed by drying to remove water (e.g., by preheating with infrared heat) and curing by dry heat fixation using dried hot air or heated contact rolls. Curing or fixation temperatures of 350-430F are used for less than 2 minutes, usually for 30 to seconds. Ordinarily, if the padded fabric is entirely polyester, curing is done at 400430F. If the fabric contains cotton or viscose rayon, apart from synthetic fibers, there is little danger of damaging cellulosic portions, but if wool is present, the curing temperature must be kept below 357F and the time must be reduced to about 30 seconds.

For durable press finishing of mixed polyester-cotton blends, after thermofixation the residual unfixed dye is removed from the fabric by scouring and the cleaned fabric is given a durable press cure at 300350F. The new dyes of the invention show an excellent diffusion rate in the polyester at the dyeing temperature and a low diffusion rate at the preferred press curing temperature of 300350F.

In order to evaluate the effectiveness of a particular dye for a given type of fiber, the dyed fiber is examined for substantivity of the color, light fastness of the color, and resistance of the color to sublimation. Specific tests for the evaluation of these important properties are described inthe examples that follow.

My invention is further illustrated by the following 1970 Technical Manual of the American Association examples: of Textile Chemists and Colorists. Dyed fabric was placed between a sandwich of undyed Dacron polyester fabric and heat was applied for 30 seconds. Subli- 4.X-D1chIorochrysazm 5 mation tests were made at 350F and 400F on goods I Charged into a 1 liter 4 neck flask, equipped with as described above. The dyeing was characterized by a stirrer thermometer and reflux condenser deep bluish-green hue. Sublimation tests showed sub- 96 chrysazin (04 mole) stantially no transfer of color, even at 400F. 400 g a The dyeings were also tested for light fastness by sub- 250 sulfuryl chloride 10 jecting them to carbon are fading in accordance with The mixture was heated slowly; reflux began about P Color Fasmess to carbon Arc Lamp 60C.-Heating was continued for and the Continuous Light Test No. 16A-l964, as detailed on temperature was maintained at 8529GT for 6 p.127, of the 1970 Technical Manual of the AATCC.

hours. The reaction mixture was agitated over- The qyeings w! l a very Slight t at 40 night. The mass was filtered and the product was hours exposure, indicating good fastness to light. washed first with EXAMPLE IV 150 ml. denatured alcohol.

It was then washed acid free with water and dried l4'Dl(p'toluldmo)'xfchloro'g'hydroxy' in an oven anthraquinone Yield: 99 g. Th. Yield: 123.6 g.(80%) 20 Charged into a 500 mo. 4-rieck flask equipped with stirrer, thermometer and short air condenser,

EXAMPLE ll 150 g. p-toluidme. I 1,4-Diani1ino-X-chloro-8-hydroxyanthraquinone It was stirred and melted at 50C. Then there was Charged into a 500 ml. 4-neck flask equipped with .added v stirrer, thermometer and short air condenser, 39 4xjdlciiiomchrysazm (0'125 mole)* and 31 g. 4,X-dichlorochrysazin (0.1 mole) 10 bone acid o 150 g aniline, and g The temperature was raised to 155 C and ma1n tained at l55-160C for 19 hours.

8 g. boric acid.

The reaction mixture was allowed to cool to 100C The temperature was raised to 150C and maintained at s for 20 hours The reaction at which temperature it was diluted portionwise mixture was allowed to cool to 40C and was di- 0 luted with g 250 ml.. methanol. 250 ml methanol The reaction mass was refluxed for 2 hours and was The mixture was heated to reflux, then allowed to 35 filtered The Cake was washed first wlth 150 ml. methanol,

cool to room tern erature' overni ht. The mass p g then with hot water. The cake was dried in an oven was filtered and the cake was sucked dry. it was 0 1 then stirred with 150 g. dimethyl formamide for 2 hours. 43 (733%) The mixture was filtered and the product was Standardization washed with hot water. The cake was dried. lt

weighed 31 g. of the theoretical yield). A color content paste was made' Charged to a ball-mill Standardization 27g. 100% color A 7 5% olor content paste was made. 45 33 g. Reax A" (sodium lignin sulphonate) and Charged to a ball-mill; 27 g. color 33 g. Reax 85A (sodium lignin sulphonate) and ditertiary acetylenic glycol Surfactant) The mixture was milled until the dispersion test was 50 satisfactory. Dyeing on polyester made by the thermofix method were green in hue, somewhat yellower in shade than those found in Example 300 g. water 2 drops Surfanol 104 (solid ditertiary acetylenic glycol surfactant). The mixture was milled until the dispersion test was Ill. Properties were comparable. satisfactory.

EXAMPLE n1 55 EXAMPLE v A dilute dispersion of g/l concentration of the dye paste of Example [I was padded on to Type 54 Dax' cron polyester fabric. After evaporation of the water, anthraqumone which leaves small dyed particles on the surface of the 60 Charged into a 500 ml 4-neck flask equipped with fabric, the dye was fixed by heating for 60-90 seconds stirrer, thermometer and short air condenser at 400430 F. This dry-heat fixation leaves some resid- .150 g. p-anisidino ual by mechanically adherring to the surface of the fab- 7 It was stirred and melted at 60C. Then there was ric. Unfixed dye was removed from the fabric by scouradded ing. 65 31 g. 4,X-dichlorochrysazin (0.1 mole), and

Sample dyeings were tested for sublimation accord- 8 g. boric acid. ing to standard AATCC Color Fastness to Dry Heat The temperature was raised to C and main- (sublimation) Test No. 117-1967T, Page 123 of the tained at 140-145C for 15 hours.

300 g. water 2 drops Surfanol 104 (solid The reaction mixture was allowed to cool to 100C 250 ml. denatured alcohol.

at which temperature it was diluted portionwise The reaction mass was refluxed for 3 hours and was with filtered hot. The cake was washed first with 250 ml. denatured alcohol. 150 ml. denatured alcohol,

The reaction mass was refluxed for 3 hours and was 5 then with hot water. The cake was dried in an oven.

filtered hot. The cake was washed first with 150 ml. denatured alcohol, Yield: 38 Th. Yield: 51 g. (74.5%)

then with hot water. The cake was dried in an oven. m A A 7 Yield: 36 g. Th. Yield: 50 g. (72%) Standardization standardization A 7.5% color content paste was made.

Charged to a ball-mill A 7.5% color content paste was made. 30 100% color Charged to a ban-m1 36 g. Reax 85 A (sodium lignin sulphonate) and 30 g. 100% color 36.3 Reax 85-A and, 333.7 g. water.

The mixture was milled until the dispersion test was satisfactory. When applied to polyester fabric by the thermofixation metohd, yellowish green hues of outstanding sublimation fastness and good 334 g. water 2 drops Surfanol 104 (solid ditertiary acetylenic glycol surfactant). Themixture was milled until the dispersion test was satisfactory. Polyester was dyed attractive green hues of excellent durability, especially to sublilight fastness were obtained. matlon' EXAMPLE VI EXAMPLE VIII 1 ,4-Di-(2,4-xylidino)-X-chloro-8-hydroxy- 2s P anthraquinone hydroxyanthraquinone Charged into a 500 ml 4-neck flask equipped i Charged into a 1 liter 4-neck flask equipped with stirrer, thermometer and short air condenser stirrer thermometer and reflux condenser 120 g, 2 i 350 ml. hot water, and 31 4 x di hl h i 1 mole), and 97.7 g. (wet cake) of l,4-dianilino-X-chloro-8- 8 g. bori a id, hydroxyanthraquinone 44 g. dry content (0.l m-

The temperature was raised to 150C and maintained at 155-l55C for 20 hour Th r ti The mixture was stirred for one-half hour. Then mixture was allowed to cool to 100C at which 35 there was added temperature it was diluted portionwise with 20 g. 50% caustic soda solution, and 250 ml. denatured alcohol. 15 g. 2-mercapto ethanol.

The reaction mass was refluxed for 2 hours and was The mixture was heated at reflux for 5 hours. The

filtered The cake was Washed first With reaction mass was allowed to cool to room tem- 150 denatured alcohol, perature. The it was neutralized to slight acidity then with hot' water. The cake was dried in an oven. i dilute hydrochloric acid The mixture was filtered and washed acid free with water. The Yield: 35 g. Th. Yield: 49.6 g. (70.5%) Cake was dried in an Oven Standardization Yield: g. Th. Yield: 48.2 g(93%). A 7.5% color content paste was made. 45 tandardization Charged to a bau'mm A 10% color content paste was made. 30 100% color I Charged to a mill 36 g. Reax 85-A (sodium lignin sulphonate) and 40 g 100% color g. Reax 85A and 310 g. water.

The mixture was milled until the dispersion test was satisfactory. Polyester colored with the produced material was a grayish-green of excellent properties, especially to sublimation.

EXAMPLE 1X 334 g. water 2 drops Surfanol 104(solid ditertiary acetylenic glycol surfactant). The mixture was milled until the dispersion test was satisfactory. When dyed on polyester, by thermofix methods, green hues of excellent durability were obtained.

EXAMPLE Vll l,4-Di-(m-chloroanilino)-X-chloro-8- hydroxyanthraquinone 4,X-dlbromochrysazin Charged into a 500 ml. 4-neck flask equipped with charged into a 1 liter 5* flask equipped with stirrer, thermometer and short air condenser stirrer thermometer and reflux condenser 31 g. 4,X-dichlorochrysazin (0.1 mole) 96 Chrysazi mole) and 120 g. m-chloroaniline, and 400 nitrobenlene- 13 g, trimethyl bur-are, The mixture was stirred and heated to C. There The temperature was raised to 170C and main- 65 as added at 6570C during 2 hours tained at l-l75C for 20 hours. 132 g. bromine. The reaction mixture was allowed to cool to C Temperature was raised to 100C during 2 hours at which temperature it was diluted portionwise and maintained at 100l05C for 18 hours. The

with reaction mixture was cooled to room temperature. The mass was filtered and the product was I washed first with 150 ml. denatured alcohol. It was then washed with hot water and dried in an oven. Yield: 135 g. Th. Yield: 159.2 g(85%).

EXAMPLE X l,4-Dianilino-X-bromo-8-hydroxyanthraquinone When the 4,X-dichlorochrysazin in Example ll was substituted with 50 g. 4,X-dibromochrysazin, 36 g'. l,4-dianilino-X-bromo-8- hydroxyanthraquinone were obtained.

A dispersion of the product when applied to polyester fabric by the therrnofixation method gave deep bluish green hues of excellent sublimation fastness and good light fastness.

EXAMPLE x1 1,4-Di-(p-toluidino )-X-bromo-8- hydroxyanthraquinone When the 4,X-dichlorochr'ysazin in Example IV was substituted with 50 g. 4,X-dibromochrysazin, the product obtained when properly dispersed and applied on polyester fabrics by the therma-fixation methods give bluish green hues of outstanding sublimation and good light fastness.

What is claimed is:

l. A method of coloring aromatic polyester textile material in deep blue-green hue comprising:

a. padding a polyester textile material with a dispersion of a dye of the formula:

wherein Z is a non-peri chlorine or bromine, R and R are members selected from the group consisting of hydrogen, chlorine, lower alkyl and lower alkoxy and n is an integer having a value of 1-2, at an elevated temperature of at least 400F,

b. drying to remove water and c. dry heat curing the dried material at a temperature of 350430F for a period of less than 2 minutes.

OH O NH- u fi A QM

where Z is chlorine or bromine, R, and R are members selected from the group consisting of hydrogen, chlorine, lower alkyl and lower alkoxy and n is an integer having a value of 1-3; Z being located in a non-peri position of the anthraquinone nucleus.

6. Polyester textile material of claim 5 in which R and R are p-Cl-l and n is l.

7. Polyester textile material of claim 5 in which R and R are H and n is l.

8. Polyester textile material of claim 5, in which R and R are p-OCG and n is l.

9. Polyester textile material of claim 5 in which R and R are CH and n is 2.

10. Polyester textile material of claim 5 in which R and R are m-Cl and n is l. 

2. A method according to claim 1 in which curing is done in the presence of dry hot air.
 3. A method according to claim 1 in which curing is done between heated contact rolls.
 4. A method according to claim 1 in which the textile material is a polyester-cotton blend.
 5. Aromatic polyester textile material dyed with a compound of the formula
 6. Polyester textile material of claim 5 in which R1 and R2 are p-CH3 and n is
 1. 7. Polyester textile material of claim 5 in which R1 and R2 are H and n is
 1. 8. Polyester textile material of claim 5, in which R1 and R2 are p-OCH3 and n is
 1. 9. Polyester textile material of claim 5 in which R1 and R2 are CH3 and n is
 2. 10. Polyester textile material of claim 5 in which R1 and R2 are m-Cl and n is
 1. 